聚合酶链式反应-变性高效液相色谱法检测5种食源性致病菌

目的建立聚合酶链式反应与变性高效液相色谱(polymerase chain reaction-denaturing high-performanceliquid chromatography,PCR-DHPLC)相结合的方法,快速检测5种食源性致病菌(沙门菌、副溶血性弧菌、福氏志贺菌、大肠埃希菌O157∶H7和单核细胞增生李斯特菌)。方法针对16S rRNA基因保守区设计引物,PCR扩增产物用变性高效液相色谱仪检测,并进行敏感性、特异性、检出率等指标测定。结果柱温61.4℃时,5种致病菌PCR产物分别呈现特异DHPLC色谱图,保留时间均为7min左右。对沙门菌、副溶血性弧菌和单核细胞增生李斯特菌检出限均为5～10CFU/ml,福氏志贺菌和大肠埃希菌O157∶H7均为1～5CFU/ml。对83株目的分离株的检出符合率为100%,38株非目的分离株检测均为阴性;对人工污染食品中的5种致病菌均可正确检出。结论该PCR-DHPLC方法具有较高的敏感性和特异性,可用于食品中5种食源性致病菌的高通量快速检测。     

北京五城区零售鲜切果蔬中重要食源性致病菌污染与耐药性研究

目的 为探究鲜切果蔬中食源性致病菌污染及耐药现状,采集北京五城区零售鲜切果蔬样品进行重要食源性致病菌检测及耐药性研究.方法 本研究采用食品微生物检验国家标准方法,分别检测金黄色葡萄球菌、沙门氏菌、单核细胞增生李斯特氏菌和大肠埃希氏菌,对目标菌分离株进行耐药性测定,并通过荧光定量聚合酶链式反应(PCR)方法筛查致泻大肠埃...     

2017—2021年河南省肉与肉制品食源性致病菌监测及部分肠杆菌耐药特征分析

目的 了解河南省肉制品中食源性致病菌的污染状况,并对肠杆菌进行血清学分型和耐药特征分析。方法 收集2017—2021年河南省郑州市等21个监测点的1 934份肉与肉制品,参考《国家食品污染物和有害因素风险监测工作手册》和《河南省食品微生物风险监测工作手册》进行沙门菌、致泻大肠埃希菌、小肠结肠炎耶尔森菌、产气荚膜梭菌、单核细胞增生李斯特菌、金黄色葡萄球菌和空肠弯曲菌等7种食源性致病菌的检测,使用微量肉汤稀释法对致泻大肠埃希菌和沙门菌进行药敏试验,分析耐药率和耐药谱等特征。结果 1 934份样品中检出478株致病菌,其中沙门菌96株,共26个血清型,以肠炎沙门菌为主;致泻大肠埃希菌82株,以肠集聚性大肠埃希菌为主;产气荚膜梭菌68株,小肠结肠炎耶尔森菌38株,空肠弯曲菌33株,单核细胞增生李斯特菌140株和金黄色葡萄球菌21株。致病菌总检出率为24.72%,调理肉制品检出率最高达到89.00%,其次为生禽肉（36.79%）和生畜肉（22.35%）。96株沙门菌对氨苄西林（71.88%）、萘啶酸（63.54%）及四环素（58.33%）高水平耐药;82株致泻大肠埃希菌对四环素（84.38%）、...     

2006-2008年北京市大兴区食品中食源性致病菌的污染状况

目的:了解北京市大兴区市售食品中食源性致病菌污染状况.方法:2006-2008年,采集大兴辖区內的10类食品,对沙门菌、大肠埃希菌0157:H7、金黄色葡萄球菌、单核细胞增生李斯特菌、空肠弯曲茼和副溶血性弧菌等6种食源性致病菌进行监测分析.结果:食源性致病菌检出率为11.96%(67/560).金黄色葡萄球菌的检出率最高(6.79%,38/560),其次为单核细胞增生李斯特菌(3.57%,20/560)和沙门菌(11.61%,9/560).560份食品中均未检出大肠埃希菌0157:H7、空肠弯曲菌和副溶血性弧菌.生牛奶中金黄色葡萄球菌检出率最高(30.67%,23/75),其次为生肉(15.29%,39/255)、鲜冻水产品(5.45%,3/55)和熟肉制品(2.67%,2/75).结论:大兴区市售食品中食源性致病菌污染较为普遍,生牛奶、生肉类、鲜冻水产品及散装熟肉制品可能是导致食源性疾病的高危食品.     

应用基因芯片技术检测肉及肉制品中5种致病菌

建立一种运用多重聚合酶链式反应(PCR)结合基因芯片技术检测大肠埃希氏菌、沙门氏菌、金黄色葡萄球菌、志贺氏菌和单核细胞增生李斯特菌5种食源性致病菌的快速、准确、灵敏的方法。分别选取编码大肠埃希氏菌的slt基因、沙门氏菌invA基因、金黄色葡萄球菌nuc基因、志贺氏菌ipaH基因和单核细胞增生李斯特菌inlA基因,并以细菌16S rDNA基因作为阳性对照,设计引物和探针,进行多重PCR扩增,产物与含特异性探针的芯片杂交。结果表明：该基因芯片可同时特异性地检测5种致病菌,多重PCR检测灵敏度为20pg,而DNA芯片检测灵敏度可达2pg;用所制备的基因芯片检测实际肉及肉制品样品,准确率高于传统培养法。所建立的基因芯片检测方法特异性好、灵敏度高,可为食源性致病菌的检测提供理想手段。     

2002-2005年北京市顺义区食品致病菌监测分析

目的了解北京市顺义区食品致病菌的污染状况。方法按照GB/T4789─2003食品微生物检验标准方法进行检验。结果2002-2005年共监测了6类食品（590份）中的4种致病菌（沙门菌、金黄色葡萄球菌、肠出血性大肠埃希菌O157：H7、单核细胞增生性李斯特菌）。检出致病菌57株,阳性率为9.7%,其中检出沙门菌2株,金黄色葡萄球菌26株,单核细胞增生性李斯特菌29株,未检出肠出血性大肠埃希菌O157：H7。6类食品中生牛奶、生畜（禽）肉类产品致病菌阳性率较高,分别为15.5%、14.5%;冰淇淋、水产品、散装熟食中也有检出,分别为5.0%、4.4%、1.9%;生食蔬菜中没有检出致病菌。结论生牛奶、生畜（禽）肉类产品是致病菌污染的主要食品,由此造成的二次污染是引起食物中毒的隐患,应该引起足够重视。     

贵州某地自制腐乳微生物污染情况研究

运用随机采样法,在贵州某地农贸市场采集到白腐乳、红油腐乳、霉豆腐各两份。根据食品微生物学检验的相关检测方法,检测菌落总数、大肠菌群、沙门氏菌、金黄色葡萄球菌、霉菌、蜡样芽孢杆菌、大肠埃希氏菌O157:H7/NM、单核细胞增生李斯特氏菌和志贺氏菌。结果显示,菌落总数、大肠菌群、蜡样芽孢杆菌的检出率为100%,霉菌检出率为66.67%,金黄色葡萄球菌检出率为33.33%;致病菌定性检测中,大肠埃希氏菌O157:H7/NM检出率为33.33%,沙门氏菌检出率为16.67%,单核细胞增生李斯特氏菌检出率为16.67%,6个样品中均未检测出志贺氏菌。通过本次试验初步评估自制腐乳的安全性,以期为贵州腐乳发酵中常见微生物污染及食用安全性评价提供参考。     

2009年嘉兴市食源性病原菌监测分析

目的监测2009年嘉兴市食品中致病菌污染状况。方法共采集275份生熟食品样品,分离沙门菌、单核细胞增生李斯特菌、大肠杆菌O157:H7、金黄色葡萄球菌和副溶血性弧菌。结果 75份生肉、水产品食源性病原菌总污染率45.3%,其中检出沙门菌6株,单核细胞增生李斯特菌12株,金黄色葡萄球菌4株,副溶血性弧菌18株。未检出大肠杆菌O157:H7。200份即食食品总污染率3.0%,以金黄色葡萄球菌污染为主。结论 2009年嘉兴市主要污染食品品种是冷藏冷冻生肉,污染的食源性致病菌以单核细胞增生李斯特菌和副溶血性弧菌为主。     

广东省江门市区2004-2008年食源性致病菌的监测

目的了解江门市区2004-2008年食品中沙门菌、金黄色葡萄球菌、单核细胞增生李斯特菌、副溶血性弧菌及肠出血性大肠肝菌(EHEC)O157∶H7的污染状况,确定上述致病菌可能污染的高危食品,为食源性疾病监测提供科学依据。方法依据国标方法,并按《广东省食源性致病菌监测计划》检测技术要求,对采集的食品样本分别进行沙门菌、金黄色葡萄球菌、单核细胞增生李斯特菌、副溶血性弧菌及EHECO157∶H7分离、生化及血清学鉴定。结果从9类626份食品中,5年共检出致病菌54株,总检出率为8.63%。其中金黄色葡萄球菌3年检出14株,检出率最高为4.83%;其次为沙门菌5年检出23株,检出率为3.67%;单核细胞增生李斯特菌5年检出16株,检出率为2.56%;副溶血性弧菌5年中仅检出1株,检出率为0.16%;未检出EHECO157∶H7。以非定型包装熟肉、生肉类污染较为严重。结论应加强非定型包装熟肉和生肉类食品食源性致病菌污染的监测。     

农产品中食源性致病菌的污染状况分析

目的了解农产品中食源性致病菌的污染状况,为政府监管提供依据。方法共抽取430份农产品样品,监测项目为沙门氏菌、单核细胞增生李斯特氏菌、金黄色葡萄球菌、大肠埃希氏菌O157:H7、霍乱弧菌、志贺氏菌、副溶血性弧菌和诺如病毒。采用全自动基因指纹分析仪对分离到的部分沙门氏菌和金黄色葡萄球菌株进行核糖体基因指纹鉴定。结果农产品中存在食源性致病菌的污染,畜禽产品中检出单核细胞增生李斯特氏菌22株、沙门氏菌17株、金黄色葡萄球菌7株;水产品中检出霍乱弧菌7株;鲜食蔬菜中检出金黄色葡萄球菌11株,72%的金黄色葡萄球菌产肠毒素。全自动基因指纹分析仪的鉴定结果和国标方法完全一致。结论应重视农产品的源头污染,加强监控。全自动基因指纹分析仪可用于食源性致病菌的快速鉴定和溯源。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press